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Applied Mathematics and Mechanics(English Edition) 1991年第9期12卷 881-890页

作者： Xu Da-peng julian Hunt Institute of Mechanics Chinese Academy of SciencesBeijing Department of Applied Mathematics and theoretical Physics University of CambridgeCambridgeBritain

A general four-layer structure linear theory for predicting the effects of arbitrarily distributed roughness change on the variations of wind speed and shear stress in the surface layer of 3D and 2D atmospheres was **... 详细信息

关键词： atmospheric boundary layer surface roughness

Nickel nanoparticles supported on nitrogen-doped carbon nanotubes are a highly active,selective and stable CO_(2) methanation catalyst

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Journal of Energy Chemistry 2021年第3期30卷 323-331页

作者： julian Godde Mariia Merko Wei Xia Martin Muhler Laboratory of Industrial Chemistry Ruhr University BochumD-44780 BochumGermany

CO_(2) methanation using nickel-based catalysts has attracted large interest as a promising power-to-gas *** nanoparticles supported on nitrogen-doped CNTs with Ni loadings in the range from 10 wt% to 50 wt% were synthesized by impregnation,calcination and reduction and characterized by elemental analysis,X-ray powder diffraction,H_(2) temperature-programmed reduction,CO pulse chemisorption and transmission electron *** Ni/NCNT catalysts were highly active in CO_(2) methanation at atmospheric pressure,reaching over 50% CO_(2) conversion and over 95% CH_(4) selectivity at 340℃ and a GHSV of50,000 mL g^(-1) h^(-1) under kinetically controlled *** small Ni particle sizes below 10 nm despite the high Ni loading is ascribed to the efficient anchoring on the N-doped *** optimum loading of 30 wt%-40 wt% Ni was found to result in the highest Ni surface area,the highest degree of conversion and the highest selectivity to methane.A constant TOf of 0.3 s^(-1) was obtained indicating similar catalytic properties of the Ni nanoparticles in the range from 10 wt%to 50 wt% Ni ***-term experiments showed that the Ni/NCNT catalyst with 30 wt% Ni was highly stable for 100 h time on stream.

关键词： CO_(2)methanation Nickel nanoparticles Carbon nanotubes Nitrogen doping

Modifications in aerosol physical, optical and radiative properties during heavy aerosol events over Dushanbe, Central Asia

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Geoscience frontiers 2021年第6期12卷 299-312页

作者： Dipesh Rupakheti Maheswar Rupakheti Xiufeng Yin julian Hofer Mukesh Rai Yuling Hu Sabur f.Abdullaev Shichang Kang State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Institute for Advanced Sustainability Studies PotsdamGermany Leibniz Institute for Tropospheric Research LeipzigGermany Physical Technical Institute of the Academy of Sciences of Tajikistan DushanbeTajikistan Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of SciencesBeijing 100101China

the location of Central Asia,almost at the center of the global dust belt region,makes it susceptible for dust *** studies on atmospheric impact of dust over the region are very limited despite the large area occupied by the region and its proximity to the mountain regions (Tianshan,Hindu Kush-KarakoramHimalayas,and Tibetan Plateau).In this study,we analyse and explain the modification in aerosols’physical,optical and radiative properties during various levels of aerosol loading observed over Central Asia utilizing the data collected during 2010–2018 at the AERONET station in Dushanbe,*** episodes were classified as strong anthropogenic,strong dust and extreme *** mean aerosol optical depth (AOD) during these three types of events was observed a factor of ~3,3.5 and 6.6,respectively,higher than the mean AOD for the period 2010–*** corresponding mean fine-mode fraction was 0.94,0.20 and 0.16,respectively,clearly indicating the dominance of fine-mode anthropogenic aerosol during the first type of events,whereas coarse-mode dust aerosol dominated during the other two types of *** was corroborated by the relationships among various aerosol parameters (AOD ***,and EAE ***,SSA and RRI).the mean aerosol radiative forcing (ARf) at the top of the atmosphere (ARf_(TOA)),the bottom of the atmosphere (ARf_(BOA)),and in the atmosphere (ARfATM) were -35±7,-73±16,and38±17 Wm^(-2)during strong anthropogenic events,-48±12,-85±24,and 37±15 Wm^(-2)during strong dust event,and -68±19,-117±38,and 49±21 Wm-2during extreme dust *** in aerosol loading enhanced the aerosol-induced atmospheric heating rate to 0.5–1.6 K day^(-1)(strong anthropogenic events),0.4–1.9 K day^(-1)(strong dust events) and 0.8–2.7 K day^(-1)(extreme dust events).the source regions of air masses to Dushanbe during the onset of such events are also *** study contributes to the understanding of dust and anthropogenic aerosols,in particular the extreme

关键词： Dust events Aerosol optical properties AERONET Dushanbe Central Asia

fused in sarcoma-amyotrophic lateral sclerosis as a novel member of DNA single strand break diseases with pure neurological phenotypes

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Neural Regeneration Research 2021年第1期16卷 110-112页

作者： Marcel Naumann julian Laubenthal Andreas Hermann Translational Neurodegeneration Section“Albrecht-Kossel” Department of NeurologyUniversity Medical Center RostockUniversity of RostockRostockGermany German Center for Neurodegenerative Diseases(DZNE)Rostock/Greifswald Center for Transdisciplinary Neurosciences Rostock(CTNR)University Medical Center RostockUniversity of RostockRostockGermany

Accumulation of DNA damage and genomic instability are believed to have crucial effects in neurodegenerative conditions such as Alzheimer’s disease,Parkinson’s disease,Huntington’s disease,premature aging diseases as well as amyotrophic lateral sclerosis(ALS)and frontotemporal dementia(fTD).Until recently these studies were largely correlative in nature,though raising the possibility that defects in the DNA damage response(DDR)underlie neurodegenerative diseases.

关键词： diseases Huntington amyotrophic

the Perception of flood Risks: A Case Study of Babessi in Rural Cameroon

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International Journal of Disaster Risk Science 2021年第4期12卷 458-478页

作者： Gertrud Buchenrieder julian Brandl Azibo Roland Balgah Research Center RISK Institute of Sociology and EconomicsUniversität der Bundeswehr München85577NeubibergGermany Leibniz Institute of Agricultural Development in Transition Economies(IAMO) 06120Halle(Saale)Germany TUM School of Life Sciences Weihenstephan Technical University Munich(TUM)85354MunichGermany College of Technology The University of Bamenda(UBa)BamendaNorth West RegionCameroon

Although risk perception of natural hazards has been identified as an important determinant for sound policy design,there is limited empirical research on it in developing *** article narrows the empirical literature *** draws from Babessi,a rural town in the Northwest Region of *** was hit by a severe flash flood in *** cross-disciplinary lens applied here deciphers the complexity arising from flood hazards,often embedded in contexts characterized by poverty,a state that is constrained in disaster relief,and market-based solutions being *** data were collected via snowball *** logistic regression analysis suggests that individuals with leadership functions,for example,heads of households,perceive flood risk higher,probably due to their role as household *** found that risk perception is linked to location,which in turn is associated with religious *** perceive floods riskier than Muslims because the former traditionally reside at the foot of hills and the latter uphill;rendering Muslims less exposed and eventually less affected by ***,public disaster relief appears to have built up trust and subsequently reduced risk perception,even if some victims remained skeptical of state disaster *** indicates strong potential benefits of public transfers for flood risk management in developing countries.

关键词： flood disaster Multinomial logistic regression Risk perception Rural Cameroon

Utilization of pH-driven methods to fortify nanoemulsions with multiple polyphenols

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food Science and Human Wellness 2024年第4期13卷 1943-1950页

作者： Hualu Zhou Bingjing Zheng David julian McClements Department of food Science and Technology College of Agricultural and Environmental SciencesUniversity of GeorgiaGriffinGA 30223USA Biopolymers and Colloids Laboratory Department of Food ScienceUniversity of MassachusettsAmherstMA 01003USA Department of food Science&Bioengineering Zhejiang Gongshang UniversityHangzhou 310018China

Simple but effective methods are required to incorporate multiple bioactive polyphenols into delivery systems to increase their dispersibility,stability and *** developed and tested three p Hdriven protocols for creating nanoemulsions loaded with multiple lipophilic *** protocols differed in how the different polyphenols were incorporated into the *** impact of these three methods on the formation,properties,and gastrointestinal fate of nanoemulsions loaded with curcumin,resveratrol,and quercetin was *** three methods produced nanoemulsions with similar initial particle properties:droplet diameters(0.15,0.16,and 0.15μm)and zeta-potentials(–59,–58,and–58 m V),***,the average encapsulation efficiencies(82%,88%,and 61%),gastrointestinal stabilities(83%,97%,and 29%)and bioaccessibilities(77%,90%,and 73%)for curcumin,resveratrol,and quercetin were somewhat *** particular,more quercetin degradation occurred using the approach that held it under alkaline conditions for extended *** general,the p H-driven method provides researchers with a versatile approach of incorporating multiple polyphenols with different characteristics into functional food and beverages using a simple and inexpensive method.

关键词： Polyphenols pH-Driven encapsulation Nanoemulsions Gastrointestinal fate functional foods

Buoyancy and turbulence-driven atmospheric circulation over urban areas

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Journal of Environmental Sciences 2017年第9期29卷 63-71页

作者： Yifan fan julian Charles Roland Hunt Yuguo Li Department of Mechanical Engineering The University of Hong KongHong KongChina Department of Earth Sciences University College LondonLondonWC1E6BTUK Malaysian Commonwealth Studies Centre CambridgeCB23RFUK

In the buoyancy and turbulence-driven atmospheric circulations（BTDAC） that occur over urban areas where the approach means wind speeds are very low（less than turbulent fluctuations and typically 3 m/sec）, the surface temperatures are significantly higher than those in the external rural areas, and the atmosphere above the mixing layer is stably stratified. In this paper, the mechanisms of BTDAC formation are studied through laboratory experiments and modelling, with additional low-level inflow from external rural areas and a divergent outflow in the opposite direction in the upper part of the mixed layer. Strong turbulent plumes in the central region mix the flow between lower and higher levels up to the inversion height. there are shear-driven turbulent eddies and weaker buoyant plumes around the periphery of the urban area. As the approach flow is very weak,the recirculating streamlines within the dome restrict the ventilation, and the dispersion of pollution emitted from sources below the inversion height leading to a rise in the mean concentration. Low-level air entrained from rural areas can, however, improve ventilation and lower this concentration. this trend can also be improved if the recirculating structure of the BTDAC flow pattern over urban areas breaks down as a result of the surface temperature distribution not being symmetrical, or as the approach wind speed increases to a level comparable with the mean velocity of circulation, or（except near the equator） the urban area is large enough that the Coriolis acceleration is significant.

关键词： Urban heat island Buoyancy and turbulence-driven Eddy structures Atmospheric circulation Pollutant dispersion

A Lagrangian mean theory on coastal sea circulation with inter-tidal transports ***

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Acta Oceanologica Sinica 2008年第6期27卷 1-16页

作者： fENG Shizuo julian JIANG Wensheng Key Laboratory of Physical Oceanography of Ministry of Education Institute of Physical Oceanography Ocean University ofChina Qingdao 266100 China

A brief review is made on the theory of the Lagrangian residual circulation and inter-tidal transports in a convectively weakly nonlinear system. In the review the emphasis is put on the systematical development of the theory and its weakness of convectively weakly nonlinear approximation. the fundamentals of a Lagrangian tidally-averaged theory on circulation with inter-tidal transport processes have been proposed for a general nonlinear coastal/estuarine system. the Lagrangian residual velocity is strictly de- fined, and it has been verified to be able to embody the velocity field of circulation. A new concept of the concentration for inter- tidal transport processes is presented. the concentration describing the inter-tidal transport processes should be a ＂Lagrangian inter-tidal concentration＂ defined and named, but not the Eulcrian tidally-averaged concentration used traditionally. the circulation described here contains a set of infinite temporal-spatial fields of velocity/concentration, each of which corresponds to a specific value of tidal phases varying continuously over one tidal cycle. When the convectively weakly nonlinear condition（ with a smaller order of eddy diffusion and sources） is approximately satisfied, a set of infinite temporal-spatial fields of velocity/concentration can be reduced to a single one.. the mass transport velocity/the Eulerian tidally averaged concentration as exhibited traditionally.

关键词： nonlinear shallow waters tide-dominating system coastal water circulation Lagrangian residual velocity Lagrangian inter-tidal concentration

Drag Reduction in a Swimming Humboldt Penguin, Spheniscus Humboldti, when the Boundary Layer is Turbulent

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Journal of Bionic Engineering 2005年第2期2卷 57-62页

作者： Alex R.Parfitt julian f.V. Vincent Centre for Biomimetic and Natural Technologies Department of Mechanical Engineering The University of Bath Bath BA2 7AY UKCentre for Biomimetic and Natural Technologies Department of Mechanical Engineering The University of Bath Bath BA2 7AY UK

An area of protruding feathers found around the beak of many penguin species is thought to induce a turbulent boun~dary layer whilst swimming. Hydrodynamic tests on a model Humboldt penguin, Spheniscus humboldti, suggest that induced turbulence causes a significant reduction in boundary layer height, flow separation, and an average of 31 % reduction in drag (1.0 m/s to 4.5 m/s). Visualisation of surface flow showed it to follow the body profile, over the feet and tail, before separating. Movement of the feet in swimming penguins correlates with steering of the bird. Induced turbulence may therefore further increase swimming efficiency by reducing the amount of foot movement required to direct the swimming bird.

关键词： drag drag reduction boundary layer turbulence penguin Spheniscus humboldti (Sphenisciformes)

Evolving concepts and opportunities in soil conservation

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International Soil and Water Conservation Research 2015年第1期3卷 1-14页

作者： julian Dumanski Consultant Sustainable Land ManagementOttawaCanada

the terrestrial landscape has changed considerably compared to that of the early 20th century when soil conservation was first *** portions of the land are already intensively managed,and the remainder is increasingly receiving human *** work on soil conservation focused attention on technological innovations,particularly control and mitigation of soil ***,land degradation has continued and actually accelerated in many parts of the world,due mainly to demands for continued economic development,using technologies that are highly *** many cases,this has been facilitated by highly inadequate and unsympathetic institutional,legislative,and policy *** paper discusses some of the new driving forces,new international programs,and new potential partners in soil ***,international efforts to mitigate land degradation are shifting from studies of the biophysical processes to improving the global,national and local enabling policy environment,as well as mainstreaming of soil conservation into national and regional policies and ***,increased emphasis is placed on economic instruments and international markets,such as carbon trading,and incorporation of non-market values in ecosystem investment,such as payment for ecosystem services,certification schemes,*** paper discusses some of the opportunities for soil conservation that accrue from these new driving forces.

关键词： Land degradation Environmental goods and services Driving forces